


The Johnny Seo Effect

by pcyikes



Category: NCT (Band)
Genre: Alternate Universe - Harry Potter Setting, Alternate Universe - Hogwarts, Enemies to Lovers, Hogwarts Professors, M/M
Language: English
Status: Completed
Published: 2019-07-19
Updated: 2019-07-19
Packaged: 2020-06-27 05:37:26
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 8,539
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19784341
Author URL: https://archiveofourown.org/users/pcyikes/pseuds/pcyikes
Summary: Slytherin Doyoung was the only person who was immune to, what he calls, The Johnny Seo Effect.All throughout his years as a student at Hogwarts, Gryffindor Johnny was his rival in all things. Years later, they return to Hogwarts as professors, and Doyoung expects for the rivalry of their past to continue. What Doyoung doesn't expect is to suddenly enjoy spending time around Johnny.





	The Johnny Seo Effect

**Author's Note:**

> hi hi  
> This is a bit shorter than I originally wanted it to be, so you can thank writers block for that.  
> Honestly, I'm just proud that I finally finished it. Anyways, I hope you all enjoy this, especially the person who submitted this prompt!

The streets of Hogsmeade were blissfully empty by the time Doyoung apparated just outside of the Three Broomsticks. He tucked his small briefcase under his arm and straightened out his robes; he didn’t want to be seen disheveled by any students. Not that any had arrived yet, but one could never be too sure. If there was one thing Doyoung hated the most, it was appearing unprofessional. 

He began to walk down the streets and toward his workplace, whistling a tune as he did so. He loved the beginning of a new year. Even if he was no longer a student, the joy that came with arriving at Hogwarts never faded. 

His shoes clicked on the pavement, all shiny and neat as he relished in the quietness surrounding him. It was his third year as a professor at the Hogwarts School of Witchcraft and Wizardry; something he still could hardly believe he was doing. 

The Headmaster had contacted him about becoming the new Transfiguration Professor when the position had opened. It was a subject he had excelled at greatly as a student. The day he interviewed for the job, he had been so unbelievably nervous; hands shaking and voice hoarse, but he had landed the job as one of the youngest professors at Hogwarts.

Making his way through the gates, Doyoung felt a rush of happiness fill him. He was lucky to have the job that he did. If someone had told him when he was 17 that he would be a professor at Hogwarts, he would’ve thought it to be unbelievable. It seemed too much like a dream.

He glanced down at his watch and frowned. If Taeyong didn’t hurry up, he would miss the sorting ceremony. 

The Great Hall was, thankfully, empty of all students. In the distance, Doyoung could hear the students beginning to arrive and thanked his lucky stars that he was off first year duty. As the head of Slytherin House and the youngest professor, he usually was tasked with informing the first years about the sorting hat process. However, this year, he had come straight from a research project in Belgium. 

Unlike in the past years, he hadn’t been able to arrive early like all of the other professors had, and so, Professor Jongdae had volunteered to cover his Head of the House duties for the night. Doyoung was thankful; he was exhausted from the work that he had been doing for the past five weeks and would’ve struggled not to show that to the first years.

At the front of the room, was the staff table. Not every seat was occupied, but he saw a flash of pink hair and smiled widely.

“Taeyong!” He called out to his best friend. “How on earth did you beat me?”

Taeyong turned from where he had been talking to Seulgi, the Charms Professor, and gave Doyoung a toothy smile. “You’re just a slowpoke.”

Doyoung resisted the urge to stick out his tongue in retaliation. He could feel the other professor's eyes on him. Instead, he simply rolled his eyes and sat down, letting out a heavy sigh.

“Hey, Doyoung,” Seulgi called out softly. “How was Belgium?”

Doyoung smiled. “Exhausting, but rewarding.” He glanced around the Great Hall. “I’m happy to be back.”

Hogwarts had always been Doyoung’s home. Even just arriving a few days later than normal had been tough for him.

Murmurs of the students carried through the hallway and into the Great Hall; the excited chatter of returning teenagers filling the castle. Doyoung straightened out his robes and sat up, eyes trained on the door.

Not a moment later, students of all the returning years bust into the Hall, faces alight with excitement. Doyoung smiled brightly as he watched the Slytherins take their seats. 

A few familiar faces stood out to him, and he waved happily back to those who acknowledged him. Jeno in particular, a Hufflepuff who was incredibly gifted in Transfiguration, jumped up and down to get his attention. Stifling a laugh, Doyoung gave him a big smile as he sat down at his table.

“Still can’t believe you got Head of Slytherin and I didn’t” Taeyong playfully grumbled next to him as the first years filed in, their faces pale but excited.

Doyoung shifted his attention to his best friend. “Well, I've been here for longer.”

Taeyong had arrived at Hogwarts as a professor only last year, something that had immensely delighted Doyoung. Finding out that his closest friend would be working alongside him had been unexpected but amazing.

“Alright alright,” The Headmaster began, effectively quieting the students. “Before we begin with the sorting, I would like to make an announcement.”

At the words, Doyoung sat up straighter, his head tilted up in interest.

“As you all know, our previous Care of Magical Creatures Professor has unfortunately retired.” 

The Great Hall remained silent, no one had particularly liked the professor. Even Doyoung, who tried to befriend every faculty member at Hogwarts.

The Headmaster clapped her hands. “But have no fear,” She smiled widely. “Please welcome your new Care of Magical Creatures Professor, Johnny Seo.”

Doyoung politely clapped, his eyes wandering to the door to look for the new professor before abruptly paling. Did she say Johnny Seo?

Through the doors, came a person Doyoung had prayed he would never see again. Johnny was taller than he had been when he was 17, his hair was longer and wilder too. But his smile, that wide toothy smile that could get him out of anything, was the same. And those mischievous eyes, Doyoung didn’t think those could ever be different.

He resisted the urge to slide down in his chair as Johnny approached the professor’s table. Beside him, Taeyoung laughed silently and Doyoung turned his glare to his best friend.

“You knew and didn’t tell me?” 

Taeyong laughed harder. “What’s the fun in that?”

A cough brought his attention back to the rest of the room and he looked up to see Johnny standing in front of him, eyes twinkling.

“Nice to see you again, Doie.”

Doyoung gritted his teeth as the other gave him one last smile before going to sit in a vacant chair at the end of the table. The clapping died down and the sorting began, but Doyoung couldn’t focus, not when Johnny sat only a few chairs away as the newest professor at Hogwarts.

Doyoung had loved his time as a student at Hogwarts. His friends were amazing, his professors were helpful, and his grades were perfect. But there was one thing that Doyoung had hated. One thing that was the bane of his existence. Johnny Seo.

\---

Doyoung remembered the first time he had met Johnny. 

It was their first year at Hogwarts, Doyoung had seen the new Gryffindor around in his classes and in the hallways but had never thought much about him. That is, until the day of Quidditch tryouts. 

His whole childhood, Doyoung had looked forward to being on the Quidditch team for whichever house he would end up in, so when the tryouts were announced, he was overjoyed. It wasn’t as if he believed he would make it as a first year, that rarely happened. He simply was excited to show the team his interest in the sport. 

He had a whole plan. He would show up to tryouts and display just how passionate he was about the game. Then, he would attend all practices and matches, so that the team would see how much he cared. Hopefully, the captain would realize his passion and keep an eye out for him in the future; thus, landing him a spot on the team in his second or third year. It was a brilliant plan.

One that Johnny Seo absolutely ruined.

The morning of the Slytherin team tryouts, Doyoung showed up to breakfast early. His nerves and excitement made it impossible for him to sleep. Little did he know, that his downfall was soon to come.

As he entered the Great Hall, he heard loud whooping coming from the room. With a roll of his eyes, he began to make his way to the Slytherin table, already used to the rowdy behavior of the Gryffindors. Suddenly, he found himself sprawled on the ground, his right arm in blinding pain.

With a groan, he looked up to see Johnny hovering above him, a worried look on his face.

“Woah man, I’m so sorry,” He bent down, eyes bright. “You okay?”

Cautiously, Doyoung moved his arm, yelping in pain at the action. Dread filled him as he took in the situation.

Furious, he lifted his gaze to glare at the Gryffindor. “You broke my fucking arm.”

Immediately, Johnny frowned and leaned down to look at Doyoung’s arm. After a moment of observation, he pulled back and gave him a small smile.

“It looks like I did.”

Anger filled Doyoung as he sat up, cradling his hurt arm to his chest. How could Johnny sound like he didn’t care at all?

“I have tryouts today.” He seethed.

Thanks to the tall oaf in front of him, his whole plan was absolutely ruined. How was he supposed to play Quidditch if his arm was completely useless?

“I’m sorry man,” Johnny said as he glanced up at his friends on the other side of the Hall. “There’s always next year?”

Doyoung stood up quickly and moved to stand in front of Johnny, his eyes burning with fire. The other stepped back cautiously, his hands raised in front of himself.

“Woah woah hey,” He said calmly. “Don’t get so worked up, it’s just Quidditch.”

Angry tears threatened to spill out of Doyoung’s eyes as he stepped away. “Just Quidditch?” He began, only to shrink back as a shock of pain pulsed through his arm.

At the action, Johnny moved forward as if to help him. 

Doyoung immediately jerked back, eyes narrowing. “Don’t touch me.”

With one last glare, Doyoung turned around and stalked off to the Infirmary. As he did so, he could hear the other Gryffindors laughing quietly to themselves and the tears finally fell.

After that, Doyoung had watched in anger as Johnny himself had made the Gryffindor team as a first year. 

\---

“How could you not tell me.”

Taeyong didn’t even look sorry at Doyoung’s demanding question. All he did was shrug slightly.

“I didn’t have time to.” 

Doyoung resisted the urge to slap his best friend on the shoulder. Taeyong had plenty of time to warn him about Johnny, he had just wanted to see his shock.

The sorting ceremony had just ended, all of the newly acquired Slytherins were at the large table, chatting it up with the older students. For a moment, Doyoung let himself swell with pride.

At least Johnny wasn’t the head of Gryffindor. He smirked to himself; that was one thing he already had Johnny beat at.

The two had gone to Hogwarts together, they had even been in the same year. However, the stereotypical rivalry between their houses, Gryffindor and Slytherin, had affected them.

Doyoung and Johnny had been rivals at everything; from the Quidditch pitch to the classrooms. Naturally, they hadn’t gotten along, their competitive sides prohibiting any slight friendship that could’ve been.

After they had graduated from Hogwarts, they hadn’t seen each other. Doyoung had participated in research around the world the few years before he had been hired as a professor at Hogwarts. The last he had heard, Johnny had been in Romania with some dragons.

He glanced over at Johnny who sat at the end of the professor table. He already had become friends with the other professors it seemed, if the laughing from the others was anything to go by. Doyoung clenched his teeth; Johnny always had been annoyingly good at making friends.

Even Taeyong had gotten along with Johnny. Doyoung had always been the odd man out when it came to The Johnny Seo Effect. Everyone loved the Gryffindor, especially during their time at Hogwarts.

Another round of laughter came from those around Johnny and Doyoung rolled his eyes. Here, Doyoung was the senior. He was more experienced than Johnny and thus, there would be nothing to compete over. 

This time, Hogwarts with Johnny Seo would be different.

\---

Frustration filled Doyoung’s chest as he took in the scene in front of him.

He had thought that Slytherins were loyal, that his students would stick by his side. Especially Jaemin.

The prefect that was his pride and joy stood at the end of the hallway conversing happily with a certain overly excited new professor. The light that filled Jaemin’s eyes as he talked to Johnny about god knows what, irked Doyoung to no end. To top it off, Jeno, Doyoung’s absolute favorite student despite the fact that the other was a Hufflepuff, was there as well.

Without any further thought, Doyoung stalked down the hallway. Students scrambled quickly out of his way, not used to the normally cooly collected Transfiguration Professor appearing so angry. 

Usually, Doyoung would like to think that he had more control over his emotions. But there was something about Johnny, who was obviously trying to steal Doyoung’s two favorite students, that pissed him off. The competitive nature within him boiled at the surface of his anger.

At his approach, Jeno brightened up. “Professor Kim!” The smile on his face was blinding. “How are you today?”

Without realizing, Doyoung relaxed a bit at the boy’s words. A small smile crept upon his face as he ruffled the other’s hair.

“Wonderful, how was your summer vacation?”

Immediately, Jeno rambled off about his visit to the mountains with his brothers and how he and Jaemin had hung out several times. Doyoung watched on in fondness, completely forgetting Johnny’s presence until the other coughed lightly.

Doyoung’s mood promptly soured.

“I was just telling these two boys about the Romanian Longhorn that I studied in Romania.” Johnny’s words were polite but his eyes were shining as Jaemin immediately let out a squeal.

“Oh yes!” He nudged Jeno. “Professor Seo knows so much about dragons. He said that we’re going to have a whole section covering them in class!”

The brightness to Jaemin’s words and the excited expression on the two boy’s faces made Doyoung smile softly despite the nasty feeling in his stomach.

Jeno tapped him softly on the arm. “He said he might even take us to Romania one day, maybe on a field trip! Wouldn’t that be exciting?”

“That’s very nice of him, isn’t it?” Doyoung said through gritted teeth.

Jeno and Jaemin simply nodded, Jeno’s voice coming out higher in pitch at his rising excitement. “Professor Seo is so cool! He even brought candy to class today!”

At the mention of class, the two boys straightened up, expressions quickly smoothing out.

“Uh,” Jaemin stuttered. “Speaking of class.”

Doyoung shook his head. “Go on, don’t be late.”

Jeno sent him a blinding smile as the two raced off down the hallway, ignoring Doyoung’s yells to slow down.

As soon as they rounded the corner, Doyoung looked back at Johnny, a frown immediately taking over his face. “What are you playing at?”

A confused expression painted Johnny’s face, his eyebrows furrowing. “What do you mean?”

Doyoung simply huffed and crossed his arms, already put up with Johnny’s feigned innocence. If there was anything Johnny was good at, it was tricking others into thinking he was completely free from blame. Doyoung knew better.

“Anyways,” Johnny continued lightly, seeming to accept that Doyoung would remain silent. “I heard you’re head of Slytherin.”

“What about it?”

A small smile dotted Johnny’s lips as he looked down at the other. He had always been so much taller than everyone else, even back in their Hogwarts days. Without realizing, Doyoung slightly lifted himself up on his toes, striving to match Johnny’s height.

The amused glint in Johnny’s eyes told him his action hadn’t gone unseen.

“Congrats Doie,” Johnny emphasized the nickname. “The position suits you.”

His words automatically ruffled Doyoung. “Don’t call me that,” He snapped, narrowing his eyes. “And what does that even mean?”

Johnny simply smiled, brushing a hand on Doyoung’s shoulder. “I’ll see you around.”

With that, the other briskly turned away and left, students staring up at him as he moved. Doyoung rolled his eyes, ignoring the tingling sensation that radiated from where the other touched his shoulder. Instead, he focused on the irritation that seeing Johnny always brought him.

With a huff, Doyoung turned on his heel and stalked back to his classroom, his expression furious. How Johnny always got under his skin, he didn’t know. As he entered the room, his class looked up at him, expressions nervous. It wasn’t like him to be late, especially on the first day of classes.

Once he made his way to the front of the room, he sighed. If he closed his eyes, he could pretend that his conversation with Johnny hadn’t just happened. After a moment, he spun around to face his third year students, plastering a bright smile on his face.

He had a job to do. 

\---

Doyoung and Johnny didn’t technically become rivals until their second year. Classes became immediately harder and more demanding, and Doyoung threw himself into them, determined to be the best. 

He hadn’t even worried about Johnny, especially since he had never seen the other study. It wasn’t until halfway through the first term that Doyoung realized he had been wrong.

It was potions class, not Doyoung’s favorite but still something he was good at. The Professor had been handing back the latest essay grades, and as always, she saved the top score for last.

That was why it confused Doyoung when she handed him his essay back. He frowned as the Professor moved to stand at the front of the classroom but continued to wait. It wasn’t usual that anyone but himself had the top score. 

“Congratulations to Johnny Seo for his essay.” The Professor said, handing the paper to a smiling Johnny.

Doyoung had been shocked. This had been his first potions class with Johnny, and he had never known the other was good at it. Something pulled at his chest as Johnny returned to his seat, a smug smile on his face.

It would be alright, Doyoung had thought. It was a fluke.

It hadn’t been.

From that day on, Johnny had been at the top of almost every class, just as Doyoung was. They alternated who got the top score, something that irked him endlessly. The worst part was that Johnny didn’t even seem to mind. He simply shot Doyoung a smug smile and continued to talk to his friends.

He became loved by everyone, the best in every class with only Doyoung himself to compete with. Doyoung had sworn to himself to beat Johnny Seo at anything and everything that he could. 

\---

Over the past few days since classes had started, Doyoung had heard nothing but praise about the new Care of Magical Creatures Professor. Just yesterday, he had entered the staff room to find Seulgi and Jongdae talking about how wonderful of a wizard Johnny was.

“Oh Doie!” Seulgi clapped excitedly. “You graduated with Johnny, right?”

Gritting his teeth, Doyoung had nodded, wincing at the squeal in delight that Seulgi emitted.

“He’s such a gentleman. I had a question about my new Puffskein and he told me everything I would ever need to know!”

The gushing hadn’t stopped there, eventually evolving into a description of just how handsome Johnny was. Something that went on for much too long, in Doyoung's opinion. I mean, how could anyone think that the disheveled mess of hair Johnny possessed was attractive?

“Do you think you could set me up?” Seulgi had asked with a mischievous expression, batting her eyelashes.

For some reason, Doyoung felt like he wanted to throw up suddenly. The idea of setting Johnny up with Seulgi made something swirl within his stomach. He shook his head quickly to rid himself from the feeling.

Seulgi was still looking up at him, and he rolled his eyes at the other professor’s antics. Logically, he knew Seulgi was joking; so why did the idea bother him so much?

Maybe it was the idea that Johnny had only been a faculty member at Hogwarts for a few weeks and everyone already loved him.

The students absolutely worshipped him. Especially since he knew so much about dragons. Everyone knew how much young people were fascinated with the species. He couldn’t believe Johnny was using dragons to win students over. 

It was absolutely not fair how quickly Johnny fit in and how everyone seemed to love him. Doyoung’s first year as a professor had been difficult, due to his young age, he had felt as if he needed to prove himself worthy of being at Hogwarts. He barely even remembered that year.

For Johnny to just waltz into Hogwarts and suddenly have everyone fawning over him was so unbelievably irritating. Doyoung huffed to himself as he thought about how the number one trouble maker in his house now worshipped Johnny. 

Donghyuck Lee was a pain. Despite being in Slytherin, the fifth year never listened to Doyoung. He was notorious for his pranks and even more so for sneaking out past curfew. 

However, for some reason, Donghyuck loved Johnny. Doyoung had seen the two interact, and it was truly puzzling. How Johnny reigned in Hogwarts’ biggest trouble maker was beyond him.

Doyoung remembered the betrayal that had filled him as he had taken in the scene of Donghyuck and Johnny laughing together in the library. Donghyuck was one of his. Granted, the kid was a major pain in the ass. But the point was that Donghyuck was a Slytherin, one of Doyoung’s favorites, and he was there, mingling with Johnny.

First Jeno and Jaemin, now Donghyuck. It appeared as if Johnny was attempting to steal all of Doyoung’s students.

\---

Doyoung wasn’t having a good day. 

First of all, he had woken up late, almost missing his first class completely. He had rushed out of his room, hair wild and robes disheveled. To make it worse, Johnny had been walking down the hallway at that exact moment, an amused smile on his lips at Doyoung’s appearance.

Then, Doyoung had lost his lesson plan. The thing about Doyoung was that he liked to plan exactly what he was going to teach each day. His summer was spent planning each year’s lesson plan, making it as perfect and helpful as he could. Without it, he was blind.

Technically, he could just wing it. It wasn’t like he wasn’t an expert in Transfiguration. But winging it wasn’t what he did.

Determined to find his lesson plan, Doyoung found himself retracing his steps from the day before, mumbling to himself under his breath as he walked down the hallway near his classroom. 

Suddenly, a presence next to him caused him to jump. With a hand over his rapidly beating heart, he turned to see Johnny standing beside him, a wide smile on his face.

“What do you want?” Doyoung asked with a scowl, not in the mood to deal with Johnny today.

Johnny expertly ignored his question. “What are you looking for?”

“Who says I’m looking for something?”

Johnny laughed quietly and ran a hand through his messy hair, almost knocking off the pair of glasses that sat tangled in the brown locks. “You’re walking in circles and staring intensely at the ground, Doie.”

The fact that Johnny could read him so well irked him endlessly. 

“I said not to call me that.” Doyoung muttered under his breath, his gaze never leaving the ground. 

Again, Johnny ignored him. The pair walked down the empty hallway in silence for a few more minutes before Doyoung became impatient.

“What do you want, Seo?” He demanded, stopping to glare up at the other.

An amused smile was present on Johnny’s face as he quirked an eyebrow up. “You need help, don’t you?”

“I don’t need your help.”

Johnny smirked, an action that was irritatingly attractive on him. Doyoung shook his head a little, appalled at his thoughts.

“You’ve been walking around for hours,” Johnny said slowly, his voice deep. “It looks like you need help. Now, what did you lose?”

Doyoung was silent for a moment before sighing and looking away. “My lesson plan.”

Johnny let out a laugh. “You do that?”

At Doyoung’s glare, Johnny held up his hands. “Fine fine,” His eyes twinkled. “When was the last time you saw it.”

Voices sounded from down the hallway and the pair turned to see a small group of students making their way toward them, the blues of their robes highlighting their house as they passed. Doyoung remained silent until after the students had rounded the corner before turning back to Johnny.

“Yesterday,” He bit his lip in thought. “I carry it around with me everywhere I go.”

“So where did you go yesterday?”

Doyoung resisted the urge to roll his eyes. “All over this stupid castle.”

For a moment Johnny was silent, his eyebrows furrowed in thought. Doyoung let his eyes travel over the other’s appearance. Like always, it was messy. His hair was too long, in desperate need of a haircut, and the glasses perched on top of his head were about to fall off. His robes were crooked and bulging in his chest area as if he were hiding something beneath them. 

Johnny coughed, breaking Doyoung out of his thoughts. “Let’s start at your room,” He smiled brightly. “Then we can work from there.”

Doyoung nodded and led the way, his mind still caught up on how unprofessional the other looked.

Once they made it to his rooms, they began to double back toward the staff room. They moved in relative silence, something that surprised Doyoung as he knew how much Johnny loved to talk. Even to him. 

Suddenly, a small noise came from Johnny’s robes. Confused, Doyoung halted in his steps and turned toward the other. To his surprise, Johnny had a blank expression on as he stared straight ahead, decidedly ignoring whatever noise was emitting from his robes. 

“Seo?”

Johnny remained silent, but his ears began to turn red. Another noise and Johnny cracked.

“You can’t tell anyone,” He all but whined, Doyoung stepping back at the sudden change in attitude. “Please Doie.”

Ignoring the horrendous nickname, Doyoung peered closer at the lump that was now moving in Johnny’s robes.

“What is that?” 

With a long sigh, Johnny reached his hand in his robes and pulled out a cat. Doyoung frowned and squinted at the creature. Wait not a cat, a Kneazle.

“What is that doing in your robes?”

At Doyoung’s question, the Kneazle yawned, mouth stretching wide. Doyoung watched as Johnny fondly scratched behind the creature’s ear. 

“Rosie doesn’t like being separated from me.” He responded, smiling down at the Kneazle.

Doyoung stared blankly at the other. “Those aren’t allowed in the castle.”

Immediately, Johnny turned to look up at him, a pout overtaking his face. The action caused Doyoung to step back, shock coursing through him. He sensed his ears turning red.

“Please don’t tell, Doie.” Johnny asked, his eyes somehow becoming impossibly wider.

Doyoung coughed and looked at the Kneazle, Rosie. The creature stared back at him calmly, seeming to be content in Johnny’s arms.

“Fine,” He sighed, looking away to avoid staring at Johnny’s pout. “But we still have to find my lesson plan.”

Johnny beamed down at him, his smile completely lighting up his face. Doyoung fought down his blush and turned away, beginning to walk down the hallways.

Once they reached the courtyard, Rosie jumped down from Johnny’s hold and began to roam the area. Her lion-like tail flicked behind her as she moved. 

Ignoring the Kneazle and her owner, Doyoung looked curiously around the courtyard. He had come there yesterday to take a break after his classes had ended for the day. Slowly making his way over to the nearest bench, he peeked underneath yet sighed when he found nothing.

A sudden noise startled Doyoung and he turned to see a small group of students conversing loudly in the far corner of the courtyard. Squinting, Doyoung saw Jaemin’s upset face in the group and immediately moved toward them.

“What’s this?” 

At the Professor’s question, the students all fell silent. Impatiently, Doyoung tapped his foot as Jaemin stepped forward, a guilty-looking Donghyuck close behind.

“Professor Kim,” Jaemin began nervously before being cut off by an angry Ravenclaw.

“Donghyuck ruined my robes, Sir.” The Ravenclaw boy seethed, holding his arms out to display the bright green paint that splattered his clothes.

Doyoung observed the boy, who he know recognized as another fifth year named Renjun. His robes were indeed ruined, completely stained with the green color. Irritation flowed through Doyoung as he turned to the troublemaker.

Donghyuck was glaring at Renjun. “Snitch,” He spat. “Why’d you have to go tell on me?”

Renjun moved forward as if to say something back and Doyoung felt his irritation spike.

“That’s enough.”

Immediately the group quieted and looked up at him. Doyoung straighten his own robes and glanced calmly over at Donghyuck.

“Mr. Lee,” The boy stared definitely back at him. “Ten points from Slytherin and detention for a week.”

Donghyuck opened his mouth to protest when Doyoung cut him off again. “And apologize to Mr. Haung.”

For a moment, the courtyard was silent. That was quickly broken when Donghyuck began to complain.

“That’s not fair, Renjun said Slytherin was a terrible house.” He stomped his foot on the ground. “Called me stupid too!”

Doyoung ignored the boy, simply raising an eyebrow in response.

“Professor Seo wouldn’t make me do this.” Donghyuck spat out at him, mouth drawn down into a pout as he looked over Doyoung’s shoulder at Johnny.

“Well, Professor Seo isn’t the head of your house, now is he, Mr. Lee?”

With a frustrated groan, Donghyuck turned to Renjun who looked far too satisfied. With gritted teeth, he apologized, obviously not meaning it in the slightest.

“Now you, Mr. Huang.”

Doyoung resisted the urge to groan when the Ravenclaw looked at him in shock, obviously not expecting Doyoung to request that he apologize. 

After a few more seconds, Renjun turned back to Donghyuck, his face red, and apologized as well. As soon as the words left his mouth, Doyoung felt himself relax.

“Detention for you as well,” He said sternly to the Ravenclaw before turning back to the group. “It’s getting late.”

The students nodded at the implication and mumbled their goodbyes before hurrying off into the castle. When the last student had disappeared, Doyoung allowed himself to sag down onto the nearest bench.

After a moment, another person sat beside him. He didn’t even have to look up to know who it was.

“That was impressive,” Johnny said lowly. “I’ve never been able to handle that stuff well.”

Doyoung snorted, bringing his head out of his palms. “Please, all the kids love you.”

“Sure, but they don’t always listen to me,” Johnny smiled softly. “One pout from Donghyuck and I let it go.”

Doyoung laughed loudly, the image of Donghyuck’s pout still fresh in his mind. 

“I’m bad at the whole discipline part of the job.”

Johnny’s sudden words surprised Doyoung. He had never heard of Johnny being bad at anything, much less admitting it. During their Hogwarts days, he had always been Mr. Perfect.

“It’s not something I relish in being good at.” Doyoung said shakily, mind wandering to Donghyuck’s sulking expression. 

“Oh please, you’re good at everything.”

Doyoung sat up straight, eyes wide as he looked at Johnny. The other looked genuine in his words as he stared at his hands. 

“Since when am I good at everything?”

Johnny let out a small laugh. “Since first year,” He shifted to look Doyoung in the eye. “It was unfair really.”

Doyoung was silent for a moment as he thought of all the years he had spent worrying about beating Johnny. It was amusing to know Johnny thought Doyoung was just as perfect as Doyoung thought Johnny to be. 

“Oh come on, you were Mr. Popular.” Doyoung said numbly, thinking of the hoards of people who always followed Johnny around.

The other snorted. “Only had about two true friends though.”

His words were almost sad sounding, and Doyoung quickly silenced whatever retort he had been about to throw. He thought of Jaehyun and Yuta, the other two Gryffindors who were always around Johnny.

Suddenly, Rosie jumped up on Doyoung’s lap, startling him from his thoughts. From beside him, Johnny let out a loud and genuine laugh as the creature immediately curled up into a ball. 

“She likes you.”

Surprised, Doyoung looked down, allowing a small smile to overtake his face at the sight. He knew Kneazles were wary of strangers, especially those who were around their wizard. Rosie let out a content sound, nuzzling her face into Doyoung’s leg.

They sat like that for a while, watching the sun disappear from the sky. The silence around them was nice, comfortable even. If 17-year-old Doyoung had been told that he would spend a whole afternoon with Johnny Seo and not want to stab himself in the eye, he would’ve never believed it.

Johnny suddenly got to his feet, picking Rosie up from Doyoung’s lap as he did so. “We still haven’t found your lesson plan,” He gestured for Doyoung to get up from the bench. “Come on.”

Obediently, Doyoung stood up, brushing dirt off of his robes as he did so. 

“Where to next?” Johnny asked, sending a blinding smile his way. 

Doyoung always went to the Owlery every Tuesday night to write home to his family. It was a self-imposed schedule that he had found comfort in back during his student days at Hogwarts. When he returned as a professor, he couldn’t help but continue the ritual.

When he told Johnny this, the other only looked at him blankly, an unknown emotion in his eyes. Doyoung pushed down the sudden irritation that rose up within him at Johnny’s strange mood. Instead, he turned on his heel and led the way to the tower. 

When they reached their destination, it was thankfully empty. Only a few owls flew about, the rest asleep all around the space. With wide eyes, Doyoung scanned the area. He had hoped that he set his lesson plan down when he had come to mail his weekly letter home last night.

Behind him, he could hear Johnny enter, struggling to hold Rosie in his arms as she attempted to launch herself at the nearest owl. Doyoung stifled a laugh at the look of panic that overtook Johnny’s face and turned away to continue searching.

He ignored all sounds of Johnny’s struggle from behind him as his eyes roamed the space. Owl droppings and some stray pieces of homework covered the floor, but no lesson plan. Just as he was about to groan in frustration, a sound of triumph emitted from behind him.

Spinning quickly on his heels, he turned to see Johnny, one arm still firmly wrapped around a struggling Rosie, and the other arm cradling a bright purple folder. 

Immediately, Doyoung’s eyes narrowed on the folder. His folder.

“You found it!” He exclaimed happily, rushing forward to take his lesson plan from the other.

Johnny chuckled, the action moving his whole chest, and nodded. Doyoung was so caught up in the joy of finally finding his lesson plan, that he failed to notice how close he was standing to Johnny until he looked up.

All breath left his lungs, his smile fading as the dull sound of his heartbeat filled his ears. Johnny’s head was tilted down to look at him, his long hair hanging over most of his face. Still, he looked handsome as he stared fondly at Doyoung. Doyoung hated to admit it, but their height difference didn’t really bother him; in fact, he kind of liked it.

Doyoung felt himself blush at his own thoughts and he took a hurried step back, ducking his head back down to look at his lesson plan. The happiness he had felt at finding it had dulled in comparison to the sudden nerves that ran through his body. 

“Uh,” He stuttered out. “Thank you for finding this.”

He didn’t look up, but he could hear the smile in Johnny’s voice. “Anytime, Doie.”

For once, Doyoung didn’t feel annoyance at the nickname. Instead, he could feel himself become redder. What was happening to him?

All he knew was that he had to get out of there. He had spent too much time with Johnny Seo. 

“Well,” Doyoung mumbled, sidestepping around the other to get to the door. “I’ll see you tomorrow.”

As he hurried out of the tower and down the stairs, he could hear Johnny’s bright laughter following him. “See you later!” He yelled after him.

The blush didn’t leave Doyoung’s face until he had shut his room’s door behind him. He leaned back against the door, panting slightly with how quickly he had walked. 

Slowly, he let his hand travel up to his cheek, confusion overwhelming him. What had just happened?

\---

Doyoung had spent most of his days at Hogwarts avoiding Johnny Seo, both as a student and as a faculty member, so he wasn’t sure why he was feeling guilty now.

It had absolutely nothing to do with the fact that Johnny had been perfectly nice helping him find his lesson plan. Doyoung had even enjoyed his time with the other.

He quickly shook his head, glaring down at his breakfast. Something had to be wrong with him; maybe he was sick?

Glancing up from his food, he felt himself slowly turn red as he saw Johnny entering the Great Hall. The other looked disheveled as always; yet somehow, it worked for him. His robes had several tears in them, and his hair was all frizzy around his head, yet his eyes were alight in happiness.

They made eye contact and Johnny waved widely. The hurt expression that overtook his face when Doyoung ignored him didn’t make him feel guilty at all. 

Distressed, Doyoung turned to Taeyong who was eating on his other side. “Do I look sick to you?”

Slowly putting his spoon down, Taeyong shifted to look his best friend in the eye. After a moment, a glint of amusement flashed across his face and he shook his head.

“You look perfectly fine,” He flicked the other in the forehead. “Why?”

Doyoung scowled and cradled his head. A glance in Johnny’s direction told him the other had stopped to talk to Donghyuck. His hands were moving excitedly as he talked, his face bright.

A wave of nauseousness flowed through Doyoung and he turned back to Taeyong who was staring at him curiously. “No reason.”

Taeyong didn’t look like he believed him but shrugged anyways before standing up and stretching. “Whatever man,” He patted Doyoung on the head, giggling when the other scowled and moved to fix his messed up hair. “See you later.”

Doyoung watched as his friend walked out of the room, his words echoing in his head. “Yeah,” He whispered to himself, thinking of how Johnny had said the same thing. “See you later.”

\---

There was one time in Doyoung’s Hogwarts years that he could recall actually getting along with Johnny.

With their bickering and competitive nature, it was no surprise that they often landed themselves in detention. The fact always angered Doyoung; despite the fact that he was a prefect, he still got sent to clean the Charms Professor’s classroom.

It also was no surprise that professors would always force the two of them to serve their detentions together in an attempt to let them work out their differences.

It was a Saturday night, a time when having detention was the worst. Doyoung sat on the ground of the classroom, scrubbing the floor with a small red towel. The door opened, and through it, came Johnny, a towel of his own clutched in his hands. 

At the other boy’s entrance, Doyoung simply rolled his eyes and continued scrubbing. He briefly wondered why the professors trusted the two of them to be alone in the classroom together. It didn’t matter, he wouldn’t let Johnny Seo pull him into any more trouble.

The pair had worked in relative silence until Doyoung began to hum. He wasn’t even aware that he was doing it at first, not even when it evolved into soft singing. Doyoung had always loved music, singing in the school’s choir was one of his favorite things to do. It made sense that he would hum to fill the cold silence of the room.

As soon as he realized what he was going, he stopped, his ear reddening at the thought that his rival had heard him. Doyoung was confident in his voice, but there was still a bit of vulnerability that came from singing.

He didn’t think Johnny had noticed until the other began to hum, the same tune that Doyoung had been singing. Shocked, Doyoung glanced up at the other only to see him staring pointedly at the ground. He looked back down at the floor, scrubbing harder and waiting for the annoyance that he usually got from being around Johnny to fill him. When it didn’t, he found himself beginning to hum along as well.

Soon, both boys sat on the ground, humming softly to themselves. Yet, as soon as the professor walked back into the classroom, they stopped humming and remained quiet for the rest of the night. 

The moment had been weird, and if Doyoung was asked about it today he would completely deny it, but it had been nice. 

\---

“Oh no,” Doyoung whispered, his ears turning red. “The Johnny Seo Effect.”

He was sitting at his desk, grading the newest round of essays the sixth years had just handed in, when he had a sudden realization. 

He, Kim Doyoung, was under The Johnny Seo Effect.

“What?”

Doyoung jerked his head up, eyes staring wide at Donghyuck, the only other person in the room besides Renjun. The two fifth years were grumpily sitting in the front of the classroom, dutifully doing their homework. It was their detention time, one that Doyoung himself was in charge of.

He quickly shook his head. “Nothing.”

Donghyuck narrowed his eyes but remained silent before going back to his work. Beside him, Renjun hadn’t even glanced up.

Doyoung sighed as he observed the two. He hated giving detentions, but he knew when it was needed. He could feel a budding dislike between the two students, and he was determined to try and make them get over it.

Horror suddenly washed over him as he realized he was doing exactly what his old professors had been doing with him and Johnny. He hit himself lightly on the forehead and looked back down at the papers in front of him.

However, he couldn’t get his mind off of Johnny Seo. He couldn’t stop thinking about the way Johnny’s too-long hair curled behind his ears, or the way his glasses always fell from where the sat perched on top of his head. He couldn’t bring his thoughts away from the bright look that always seemed to fill Johnny’s eyes, even when he was teasing others. 

God, Doyoung thought to himself as he closed his eyes, he was fucked.

Just that afternoon, only hours before Donghyuck and Renjun’s detention, Doyoung had run directly into Johnny. As a result, his papers had gone flying. Immediately, irritation had filled him, yet it had quickly faded when Johnny had smiled widely at him and apologized, bending down to pick up the fallen essays. 

Doyoung had blushed like an absolute idiot before scowling at the other and stomping away, ignoring the soft laughter that followed him.

Renjun sneezed and Doyoung glanced up blearily before resting his head in his hands. Every interaction he had with Johnny since the other had helped him find his missing lesson plan had just been weird. He didn’t understand it; it wasn’t like anything particularly special had happened between them that day. 

He wanted to ask Taeyong for help, but he knew the other would only laugh at him. The idea made him pout.

“Professor Kim?”

Doyoung looked up quickly, wiping the expression off of his face. “Yes?”

Renjun was looking at him with wide eyes. “Are you alright?”

Donghyuck stifled a laugh, receiving a glare from both of the others. “Suck up.” He muttered.

The look of irritation that passed over Renjun’s face was strong enough for Doyoung to speak up. He was desperate to change the subject before the two got into a real fight.

“I’m fine Mr. Haung, thank you.”

Renjun gave him a small smile before shooting another glare at Donghyuck. Doyoung sighed to himself, turning back to his essays and ignoring the screech of the chair as Renjun kicked Donghyuck in the shin.

Just as he was finally getting into the essay in front of him, his classroom door burst open. Startled, Doyoung looked up to see Johnny standing at the threshold, panting heavily.

“Seo,” Doyoung stood up, eyebrows furrowing. “Are you alright.”

Johnny simply stared at him for a moment before straightening out and fixing his robes as much as he could.

“Could I speak with you for a moment, please?”

Doyoung raised an eyebrow at that, glancing at the two students who looked just as confused as he did before nodding.

“Sure,” Johnny at his response. “But it can’t take long.”

Doyoung pointedly looked at Donghyuck and Renjun who seemed to be hanging onto their every word. To his surprise, Johnny flushed before nodding quickly.

Still confused, Doyoung exited his classroom, following Johnny out into the hallway. At this time of night, the castle was nearly empty. A small noise alerted Doyoung to the presence of Rosie who was sitting patiently on a nearby ledge.

“Seriously?” Doyoung asked, exasperated.

Johnny smiled sheepishly and scratched the back of his neck. “She gets lonely.”

Doyoung snorted and moved forward to pet Rosie, admiring the Kneazle’s spotted coat and smiling when she began to purr. Beside him, Johnny shifted uncomfortably.

“What is it?”

There was silence for a moment before Johnny cleared his throat. At the noise, Doyoung looked up from Rosie, eyes wide and curious.

“I uh,” Johnny looked a little like he was about to pass out. “I just wanted to tell you that I really enjoyed spending time with you the other day.”

Immediately Doyoung flushed, his hand falling from where it had been petting Rosie. “I enjoyed that too.”

His words sounded weak, but they were genuine. As hard as it was to admit, his time with Johnny had been fun. Besides, he had already come to terms with the fact that he was under The Johnny Seo Effect.

Johnny seemed to stand straighter at his admission. “And well,” His eyes darted around widely, looking everywhere but at Doyoung. “I was wondering if you wanted to do it again sometime.”

Doyoung tilted his head to the side. “You lost your lesson plan?”

“No no,” Johnny laughed nervously. “I’m not one to have a lesson plan.”

A spark of irritation rose up at Johnny’s simple words. Still confused yet leaning on the brink of annoyance, Doyoung spoke up. 

“What’s that supposed to mean?”

A panicked look was on Johnny’s face, something that Doyoung began to ignore as he crossed his arms over his chest and tapped his foot. 

“That’s not what I meant,” A bead of sweat ran down the side of Johnny’s face. “It’s great that you have a lesson plan, admirable really. The best professors use them.”

Doyoung couldn’t tell if the other was mocking him or not. The thought made his stomach sink; he had just admitted to himself that he enjoyed being around Johnny, and now he was making fun of him. Frustrated, Doyoung turned to go back into his classroom when a hand wrapped around his wrist.

With a tug, Johnny spun him back around so that they were facing each other again. “I’m trying to ask you out.”

Johnny’s sudden words stunned Doyoung. His mouth felt like it was full of cotton as he simply stared at the other. 

“On a date.”

The clarification wasn’t completely necessary, but it snapped Doyoung out of his trance. 

“Why?”

Johnny smiled, his nervousness seeming to disappear a little. In the back of his mind, Doyoung registered that Johnny’s hand was still clutching his wrist, his thumb rubbing small circles into the skin.

“Because I like you, Doie.”

There it was again, that damned nickname. Doyoung didn’t like it, but he had to admit every time Johnny said it, he got butterflies. 

“I, well,” Doyoung stuttered, his face turning red. “Now?”

Johnny tilted his head in consideration. “That’s not what I was thinking, but why not?”

“I have to monitor detention though.”

Johnny gave him a fond smile. “They’ll be fine on their own.”

“And I have essays to grade.”

“I’ll help you later.”

Doyoung’s mind seemed to turn to mush as he tried to think of more things he had to do. “I have to feed my goldfish.”

Johnny let go of his wrist slowly, yet he didn’t step away. 

“Do you want to or not?”

Their chests were still touching; Doyoung was worried that Johnny might be able to hear his rapid heartbeat as he thought about the other’s question.

He took in Johnny’s appearance. His eyes, roaming over the familiar wild hair and bright eyes.

“Yes.” He breathed out.

Immediately, a smile broke out onto Johnny’s face and he moved to take Doyoung’s hand in his own. The action caused Doyoung to blush as the other pulled him down the hallway, obviously excited. Behind them, Rosie followed lazily.

“Wait,” Doyoung said quickly, pulling them to a stop. “I was serious about the detention.”

Johnny moved closer to him, a fond smile on his lips. “They’ll be fine.”

Doyoung found himself pouting at the words, still concerned about the two students. Johnny’s eyes seemed to zero in on the movement.

Before he could say anything else, there was a sudden soft pressure on his lips and then it was gone. Shocked, Doyoung stared up at Johnny who was smiling mischievously at him.

“Don’t worry so much,” Johnny said playfully as he began to walk backwards down the hallway “Let’s go.”

Still in a daze, Doyoung followed. He raised his hand up to his still tingling lips, a blush lightly taking over his cheeks. Up ahead, Johnny was still smiling at him. At the sight, Doyoung dropped his hand from his lips and ran after the other, his competitive nature coming out.

The next day, the students would be whispering about the two professors who had been running through the hallways late at night together. They would be talking about how Donghyuck and Renjun claimed the two professors had kissed. They would be talking about a lot of things, but Doyoung wouldn’t mind. He wouldn’t even mind when Taeyong teased him about it for weeks. 

Doyoung had fallen for The Johnny Seo Effect.


End file.
